The growing trend is a challenge to the IRS from the churches, and may jeopardize their all-important tax-exempt status. But some pastors and church leaders said they are willing to defy the law to defend their right to freedom of speech.

Pastor Dan Fisher from Trinity Baptist Church in Yukon, Okla., who took part in today's challenge, said should be allowed to discuss politics with their congregation.

Separation of church and state is not in the Constitution, but the government uses tax exemption as a means to enforce that notion, he added.

"The crowd applauded, and said it was wonderful," Fisher said of his sermon this morning. "I can't say that everyone was happy, but no one came up to me to complain."

Federal tax law, established in 1954, prohibits churches and tax exempt entities from endorsing or opposing political candidates.

Pulpit Freedom Sunday is an initiative organized by the Alliance Defense Fund, a conservative Christian nonprofit organization, which according to its website seeks to "defend the right to hear and speak the Truth through strategy, training, funding, and litigation."

"We believe that a pastor has a right to speak whatever he believes without fearing the government will somehow censor what he says or threaten to take away his tax exemption," ADF spokesman Erik Stanley said.

He said the group believes that the 1954 amendment, sponsored by then Sen. Lyndon Johnson, D-Texas, is a violation of the Constitution. According to the ADF, the government's monitoring of the content of pastors' and churches' speech is a violation of the Free Speech Clause.

The IRS said they'd be keeping an eye on the planned activities.

"We are aware of recent press reports, and will monitor the situation and take action as appropriate," IRS spokesman Robert Marvin said.

In 2008, 33 pastors took part in the first Pulpit Freedom Sunday, when they defiantly spoke of politics to their congregation. Though not an election year, many also participated in 2009.

According to Stanley, even though all the pastors involved recorded their sermons and sent them to the IRS, only one church was investigated by the IRS, and the audit was dropped after several months.

This year the numbers have tripled and the participating pastors again will be videotaping their sermons and sending them directly to the IRS.

"The whole goal is to foster a lawsuit where we could challenge the constitutionality of the law," Stanley said. "We believe if a federal judge looked at the constitutionality of what the IRS has done, it wouldn't take long for the judge to strike it down as unconstitutional.

"It's entirely appropriate to use the separation of church and state to tell government it has no business being in the pulpits of America," he said. "This is about a pastor's right of free speech."

He said other than challenging the law, there is no political agenda.

"We make it a practice not to ask in advance [which candidates or political party a pastor might support] because for us it doesn't matter," Stanley said. "We believe pulpit freedom is for any pastor."

Pastors and Churches Divided

But not all pastors and churches agree that Pulpit Freedom Sunday will do anything to help the cause.

David Shelley, pastor of Smith Springs Baptist in Tennessee, is defying the clause for the second time this year by throwing his support behind several Republican candidates.

"My support for these candidates has nothing to do with their party or their skin color or any other non-biblically related issue," he said.

Shelley, like many other pastors, is hoping that the IRS does come after him, according to The Tennessean newspaper.

"We're the ones that have equity with the thousands of people that attend this church," Pastor Steve Riggle of Grace Community Church in Houston said in an ADF video.

"I don't run their lives, I don't tell them what to do, but I'm going to speak into their lives, and if I'm not speaking into their lives on the issues that have made the nation great, and the issues that God cares about, then who is?" he said.

Rev. Barry Lynn, executive director of Americans United for the Separation of Church and State, has made it clear that participating churches have plenty to lose.

"Tax exemption is not a right; it's a privilege that comes with certain restrictions," Lynn said.